NURS 611ADVANCED PATHOPHYSIOLOGY EXAM 3 ACTUAL EXAM -

NURS 611(ADVANCED PATHOPHYSIOLOGY) EXAM 3 ACTUAL EXAM -

NURS 611(ADVANCED PATHOPHYSIOLOGY) EXAM 3 ACTUAL EXAM

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NURS 611(ADVANCED PATHOPHYSIOLOGY) EXAM 3 ACTUAL EXAM -

• What are clinical manifestations of hypothyroidism?
• Intolerance to heat, tachycardia, and weight loss
• Oligomenorrhea, fatigue, and warm skin
• Restlessness, increased appetite, and metrorrhagia
• Constipation, decreased heat rate, and lethargy

The lower levels of thyroid hormone result in decreased energy metabolism, resulting in constipation, bradycardia, and lethargy, thus eliminating the remaining options.

• Thyroid-stimulating hormone (TSH) is released to stimulate thyroid hormone (TH) and is

inhibited when plasma levels of TH are adequate. This is an example of:

• Positive feedback
• Neural regulation
• Negative feedback
• Physiologic regulation

Negative feedback. Feedback systems provide precise monitoring and control of the cellular environment. Negative feedback occurs because the changing chemical, neural, or endocrine response to a stimulus negates the initiating change that triggered the release of the hormone. Thyrotropin-releasing hormone (TRH) from the hypothalamus stimulates TSH secretion from the anterior pituitary. Secretion of TSH stimulates the synthesis and secretion of THs. Increasing levels of T4 and triiodothyronine (T3) then generate negative feedback on the pituitary and hypothalamus to inhibit TRH and TSH synthesis.

3. Lipid-soluble hormone receptors are located:

• Inside the plasma membrane in the cytoplasm
• On the outer surface of the plasma membrane
• Inside the mitochondria
• On the inner surface of the plasma membrane

Inside the plasma membrane in the cytoplasm. Lipid-soluble hormone receptors are located inside the plasma membrane and easily diffuse across the plasma membrane to bind to either cytosolic or nuclear receptors.

• The releasing hormones that are made in the hypothalamus travel to the anterior

pituitary via the:

• Vessels of the zona fasciculata
• Hypophyseal stalk
• Infundibular stem
• Portal hypophyseal blood vessels

Portal hypophyseal blood vessels. Releasing and inhibitory hormones are synthesized in the hypothalamus and are secreted into the portal blood vessels through which they travel to the anterior pituitary hormones.

• Which mineral is needed for thyroid-stimulating hormone (TSH) to stimulate the

secretion of thyroid hormone (TH)?

• Iron
• Iodide
• Zinc

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NURS 611(ADVANCED PATHOPHYSIOLOGY) EXAM 3 ACTUAL EXAM -

• Copper

Iodide. TSH, which is synthesized and stored in the anterior pituitary, stimulates secretion of TH by activating intracellular processes, including the uptake of iodine necessary for the synthesis of TH.

• What effect does hyperphosphatemia have on other electrolytes?
• Increases serum calcium
• Decreases serum magnesium
• Decreases serum calcium
• Increases serum magnesium

Decreases serum calcium. Hyperphosphatemia leads to hypocalcemia. Remember that phos and calcium are inversely related.

• Insulin transports which electrolyte in the cell?
• Potassium
• Sodium
• Calcium
• Phosphorus

Potassium. Insulin facilitates the intracellular transport of potassium, phosphate, and magnesium.

• Which second messenger is stimulated by epinephrine binding to a β-adrenergic

receptor?

• Calcium
• Inositol triphosphate (IP3)
• Diacylglycerol (DAG)
• Cyclic adenosine monophosphate (cAMP)

Cyclic adenosine monophosphate (cAMP). Second-messenger molecules are the initial link between the first signal (hormone) and the inside of the cell. For example, the binding of epinephrine to a β adrenergic–receptor subtype activates (through a stimulatory G protein) the enzyme, adenylyl cyclase. Adenylyl cyclase catalyzes the conversion of adenosine triphosphate (ATP) to the second messenger, 3', and 5'-cAMP.

• Regulation of the release of catecholamines from the adrenal medulla is an example of

which type of regulation?

• Negative feedback
• Neural
• Positive feedback
• Physiologic

Neural. The release of hormones occurs either in response to an alteration in the cellular environment or in the process of maintaining a regulated level of certain hormones or certain substances. Several different mechanisms, one of which is neural control (e.g., stress-induced release of catecholamines from the adrenal medulla), regulate the release of hormones.

• Which hormone does the second messenger calcium (Ca

++

• bind to activate

phospholipase C through a G protein?

• Angiotensin II
• Estrogen
• Thyroxine

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NURS 611(ADVANCED PATHOPHYSIOLOGY) EXAM 3 ACTUAL EXAM -

• Testosterone

Angiotensin II. Ca ++ is considered an important second messenger that facilitates the binding of a hormone (e.g., norepinephrine, angiotensin II) to a surface receptor, activating the enzyme phospholipase C through a G protein inside the plasma membrane.

11. The control of calcium in cells is important because it:

• Is controlled by the calcium negative-feedback loop.
• Is continuously synthesized.
• Acts as a second messenger.
• Carries lipid-soluble hormones in the bloodstream.

Acts as a second messenger. In addition to being an important ion that participates in a multitude of cellular actions, Ca ++ is considered an important second messenger.

• Where is antidiuretic hormone (ADH) synthesized, and where does it act?
• Hypothalamus; renal tubular cells
• Anterior pituitary; posterior pituitary
• Renal tubules; renal collecting ducts
• Posterior pituitary; loop of Henle

Hypothalamus; renal tubular cells. Once synthesized in the hypothalamus, ADH acts on the vasopressin 2 (V2) receptors of the renal duct cells to increase their permeability.

• How does a faulty negative-feedback mechanism result in a hormonal imbalance?
• Hormones are not synthesized in response to cellular and tissue activities.
• Decreased hormonal secretion is a response to rising hormone levels.
• Too little hormone production is initiated.
• Excessive hormone production results from a failure to turn off the system.

Excessive hormone production results from a failure to turn off the system. Negative- feedback systems are important in maintaining hormones within physiologic ranges. The lack of negative-feedback inhibition on hormonal release often results in pathologic conditions. Excessive hormone production, which is the result of the failure to turn off the system, can cause various hormonal imbalances and related conditions.

• A deficiency of which chemical may result in hypothyroidism?
• Iron
• Zinc
• Iodine
• Magnesium

Iodine. The only cause of hypothyroidism from among the provided options is a deficiency of endemic iodine.

• What imbalance lessens the rate of secretion of parathyroid hormone
• Increased serum calcium levels
• Decreased serum magnesium levels
• Decreased levels of thyroid-stimulating hormone
• Increased levels of thyroid-stimulating hormone

The overall effect of parathyroid hormone (PTH)is to increase serum calcium and to decrease serum phosphate concentration.

• Which condition may result from pressure exerted by a pituitary tumor?